Push-to-charge mechanism for lancing device

ABSTRACT

A lancing device has a charging mechanism that operates to convert an external push action by a user to an internal pull action that retracts and charges a lancet for use in a lancing stroke. In some embodiments, the charging mechanism includes a user-actuated charging push-button, a reverse charging member coupled to a lancet carrier, and a reverse-motion conversion member coupled therebetween. Depressing the user-actuated member in a first longitudinal direction causes transverse movement of the conversion member, which in turn causes longitudinal retraction of the reverse charging member and the lancet carrier coupled thereto in a second longitudinal direction opposite the first direction, thereby charging a drive mechanism of the lancing device. In other embodiments, a rack-and-pinion gear mechanism provides the same push-to-pull functionality.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. Non-Provisional patentapplication Ser. No. 14/026,129 filed Sep. 13, 2013, which claims thepriority benefit of U.S. Provisional Patent Application Ser. No.61/700,634 filed Sep. 13, 2012, the entireties of which are herebyincorporated herein by reference for all purposes.

TECHNICAL FIELD

The present invention relates generally to the field of medical devices,and more particularly to a lancing device for blood sampling and testinghaving an innovative charging mechanism.

BACKGROUND

Lancing devices are utilized for penetrating the skin of a human oranimal subject at a lancing site to obtain a sample of blood or otherbody fluid for medical testing, as in blood-typing or blood-glucosetesting. Known lancing devices commonly include a housing containing adrive mechanism, a charging mechanism for energizing the spring or otherdrive means of the drive mechanism, and a release mechanism forreleasing the drive mechanism upon actuation. U.S. patent applicationSer. No. 13/005,181 (Pub. No. US 2011/0196261) and U.S. patentapplication Ser. No. 12/641,674 (Pub. No. US 2010/0160942), which areincorporated herein by reference, show example lancing devices.

A lancet is typically propelled by the drive mechanism from a retractedposition within the housing to an extended position wherein a sharp tipportion of the lancet projects from the housing to prick the subject'sskin at a desired lancing site. Many known lancing devices use a drivemechanism that is charged or energized by pulling the drive mechanism toa retracted position. This results in the user having to perform thecharging procedure by pulling the charging mechanism away from the bodyof the lancing device. Charging the drive mechanism by pulling thecharging mechanism away from the body of the lancing device can presentchallenges to users with reduced manual dexterity, and may require thesubject or user to use two hands to hold the device body and pull thehandle until the device is charged and ready to activate.

Accordingly, it can be seen that needs exist for improved systems andmethods for charging lancing devices. It is to the provision of improvedlancing devices and methods of operation and use thereof that thepresent invention is primarily directed.

SUMMARY

In example embodiments, the present invention relates to lancing deviceshaving an improved charging mechanism. The charging mechanism operatesto convert an external push action by a user to an internal pull actionthat retracts and charges a lancet for use in a lancing stroke.

In one embodiment, the charging mechanism retracts and charges a lancetcarrier via a cam-driven motion-conversion member with two cam surfaces.The charging mechanism includes an actuator member and a reversecharging member constrained to move only in an axial direction, and theconversion member which is movably mounted therebetween and constrainedto move only in a transverse direction. Pushing actuation of theactuator member in an axial-push direction causes one of the camsurfaces to produce transverse movement of the conversion member, whichin turn causes the other one of the cam surfaces to retract the reversecharging member in an axial-push direction, thereby retracting thelancet carrier coupled thereto to a charged position.

In another embodiment, the charging mechanism retracts and charges alancet carrier via a rack-and-pinion gear mechanism that provides thesame push-to-pull functionality. In this embodiment, the chargingmechanism includes two rack gears engaging one pinion gear. Pushingactuation of the actuator member in an axial-push direction causes oneof the rack gears to rotate the pinion gear, which in turn causes theother one of the rack gears surfaces to retract the reverse chargingmember in an axial-push direction, thereby retracting the lancet carriercoupled thereto to a charged position.

In another embodiment, the invention relates to a charging mechanism forinclusion in a lancing device having a drive mechanism with a lancetcarrier that holds a lancet. The charging mechanism retracts and chargesthe lancet carrier to a charged position where it interacts with thedrive mechanism for reliable retention in the charged position. Thecharging mechanism can be of a cam-driven or rack-and-pinion type asdescribed herein, or of another type that converts an external pushaction by a user to an internal pull action that retracts and charges alancet for use in a lancing stroke.

And in another embodiment, the invention relates to a method forcharging a lancing device. The method includes slidably mounting acharging mechanism within a portion of the lancing device, movablymounting a conversion member with a portion of the charging mechanism,movably mounting a portion of the lancet carrier with the conversionmember, pressing the charging mechanism into the lancing device, forcingmovement of the conversion member in a direction transverse to themovement of the charging mechanism, and moving the lancet carrier in adirection generally opposite the direction of movement of the chargingmechanism to charge the lancing device.

These and other aspects, features, and advantages of the invention willbe understood with reference to the drawing figures and detaileddescription herein, and will be realized by means of the variouselements and combinations particularly pointed out in the appendedclaims. It is to be understood that both the foregoing generaldescription and the following brief description of the drawings anddetailed description of the invention are exemplary and explanatory ofpreferred embodiments of the invention, and are not unnecessarilyrestrictive of the invention, as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front perspective view of a lancing device according to afirst example embodiment of the present invention.

FIG. 2 is a rear perspective view of the lancing device of FIG. 1.

FIG. 3 shows the lancing device of FIG. 1 with portions of its housingremoved to show internal components thereof.

FIG. 4 is a partially-exploded view of the lancing device of FIG. 3showing a charging mechanism.

FIG. 5 is a further-exploded view of the charging mechanism of FIG. 4.

FIG. 6 is a bottom perspective exploded view of the charging mechanismof FIG. 5.

FIG. 7 is a top view of a motion-conversion member of the chargingmechanism of FIG. 5.

FIG. 8 is an exploded view of the lancing device of FIG. 1.

FIGS. 9A-D are top views of the lancing device of FIG. 1, with portionsof its housing removed, showing the sequential operational movement ofthe charging mechanism between a neutral position, a charged position, aready position, and a fully extended position of a lancing stroke.

FIG. 10 is a front perspective view of a lancing device according tosecond example embodiment of the present invention, with portions of itsexternal housing moved to show internal components thereof.

FIG. 11 is an exploded view of the lancing device of FIG. 10.

FIGS. 12A-D are top views of the lancing device of FIG. 10, withportions of its housing removed, showing the sequential operationalmovement of the charging mechanism between a neutral position, a chargedposition, a ready position, and a fully extended position of a lancingstroke.

DETAILED DESCRIPTION OF EXAMPLE Embodiments

The present invention may be understood more readily by reference to thefollowing detailed description of the invention taken in connection withthe accompanying drawing figures, which form a part of this disclosure.It is to be understood that this invention is not limited to thespecific devices, methods, conditions or parameters described and/orshown herein, and that the terminology used herein is for the purpose ofdescribing particular embodiments by way of example only and is notintended to be unnecessarily limiting of the claimed invention. Any andall patents and other publications identified in this specification areincorporated by reference as though fully set forth herein.

Also, as used in the specification including the appended claims, thesingular forms “a,” “an,” and “the” include the plural, and reference toa particular numerical value includes at least that particular value,unless the context clearly dictates otherwise. Ranges may be expressedherein as from “about” or “approximately” one particular value and/or to“about” or “approximately” another particular value. When such a rangeis expressed, another embodiment includes from the one particular valueand/or to the other particular value. Similarly, when values areexpressed as approximations, by use of the antecedent “about,” it willbe understood that the particular value forms another embodiment.

With reference now to the drawing figures, wherein like referencenumbers represent corresponding parts throughout the several views,FIGS. 1-9D show a lancing device 10 according to a first exampleembodiment of the present invention. The lancing device 10 includes acharging mechanism, an actuator mechanism, a drive mechanism, and ahousing 20 for these components. The drive mechanism includes a lancetcarrier 80 that carries a lancet 89. The charging mechanism is operableto charge the drive mechanism, and the actuator mechanism is operable torelease the lancet carrier to be driven by the charged drive mechanismto propel the lancet carrier (and thus the lancet) through a lancingstroke.

The details of the housing 20, lancet carrier 80, actuator mechanism,and drive mechanism depicted and described herein are representative andnot limiting of the invention. Thus, other conventional housings, lancetcarriers, actuator mechanisms, and/or drive mechanisms can be used withgood results, as long as they are modified to include cooperatingfeatures that permit and do not interfere with the push-to-pullfunctionality provided by the charging mechanism.

Referring primarily to FIGS. 1-3, in the depicted embodiment the housing20 is elongate and thereby defines a longitudinal axis. The housing 20includes upper and lower housing shells 22 a, 22 b, and a forward orproximal end 24 defining a lancet opening through which at least a sharptip portion of the lancet projects at the extended position of thelancing stroke to penetrate the skin of a subject. The housing 20 holdsthe lancet carrier 80, with the lancet carrier movably mounted in thehousing for traversing the lancing stroke. In one form, the housing 20has a lengthwise dimension in an axial direction between its forward orproximal end 24 and its rear or distal end 26 that is greater than itsside-to-side width in a transverse dimension, which in turn is generallyequivalent to or greater than its thickness from top to bottom. Thehousing can be constructed from a substantially rigid and durablematerial, for example a plastic or composite. In other exampleembodiments, the housing has other shapes and forms (e.g., disc-shaped,only one or more than two shell pieces, etc.).

Referring primarily to FIGS. 1-2 and 8, the lancing device 10 optionallyincludes a removable endcap 40 and/or a lancet-ejection mechanism 50.Removal of the endcap 40 allows access for removal and replacement ofthe lancet 89 after use, for example by actuation of the ejectionmechanism 50. Further optional, the endcap 40 can provide adjustment tothe depth of penetration of the lancet tip projecting therethrough,wherein a portion of the endcap can move (e.g., rotate) relative toanother portion of the endcap or housing such that the depth ofpenetration of the lancet tip is adjustable. In example forms, theejection mechanism 50 movably mounts within an elongated opening along aside of the housing 20 and extends within the housing to selectivelyengage and eject the lancet 89 after use. For example, the ejectionmechanism 50 can include an elongate finger 52 extending with a tooth 54projecting generally transversely therefrom. The tooth 54 remains withina defined channel of the inner drive core 70 and a channel of the collar82. The ejection mechanism 50 is actuated to force the tooth 54 againstthe lancet 89 within the collar 82, thereby ejecting the same therefrom.In other embodiments, a conventional endcap and/or ejection mechanismcan be incorporated into the lancing device.

Referring primarily to FIGS. 3-6 and 8, details of the drive mechanismwill now be described. In the depicted embodiment, the drive mechanismincludes an inner drive core 70 that is engaged in a fixed positionwithin the housing 20 by one or more inter-engaging surface features 25,74. For example, as shown in detail in FIG. 4, the inter-engagingfeatures can include a retaining channel 25 formed within the housing 20and one or more tabs 74 extending from the inner drive core 70 andretained within the channel to retain the drive core in a fixed positionrelative to the housing. The inner drive core 70 can be provided by aseparate part assembled to the housing 20, or its features can beincorporated into the housing and thus form an integral part thereof. Inother embodiments, the male/female inter-engaging features arereversed/switched and/or or the inner drive core is engaged in a fixedposition within the housing by other inter-engaging features such astabs and slots, pins and holes, or other conventional fixing structures.

The drive mechanism further includes the lancet carrier 80 that carriesthe lancet 89. The lancet carrier 80 translationally slides within anaxial bore or channel extending longitudinally through or along theinner drive core 70. In the depicted embodiment, the lancet carrier 80has a collar or sleeve 82 at a proximal/forward end thereof forreleasably engaging a lancet 89, and a distal/rear end generallyopposite thereto includes resiliently flexing fingers 83 for providingengagement with a spring retainer 86 (see FIGS. 5-6). In alternativeembodiments, the lancet carrier is of a conventional type. For example,in some embodiments the lancet and carrier are a single part that isreplaceable (in multi-use embodiments) and/or non-replaceable (indisposable embodiments). And in other embodiments, the lancet carriersequentially engages a series of lancets in a cartridge.

In addition, the drive mechanism further includes a drive spring 92 forpropelling the lancet carrier 80 forward through an advancing portion ofthe lancing stroke and a return spring 94 for retracting the lancetcarrier backward through a return portion of the lancing stroke. Inexample embodiments, the drive spring 92 and the return spring 94 areretained on the lancet carrier 80 between a medial portion of the lancetcarrier defining outwardly projecting wings 84 and the spring retainer86 coupled to the resiliently flexing fingers 83 of the lancet carrier(see FIG. 8). For example, the drive spring 92 can be retained betweenthe distal ends of the wings 84 and a distal wall (unshown) of the innerdrive core 70, and the return spring 94 can be engaged between atransverse arm 103 (see FIG. 4) of a reverse-motion charging member 102and the spring retainer 86. In other embodiments, a single spring isprovided that drives and retracts the lancet and that is mounted inplace by conventional spring-constraining structures.

The lancet carrier 80 is mounted to and travels axially with the reversecharging member 102. The reverse charging member 102 can be provided by,for example, the depicted L-shaped link or another link operablyconnecting the lancet carrier to the charging mechanism. In the depictedembodiment, the elongate distal portion of the lancet carrier 80 extendsthrough a bore 104 (see FIG. 8) of the transverse arm 103 of the reversecharging member 102 (see FIGS. 5-6), with the resiliently flexingfingers 83 of the elongate distal portion of the lancet carrierretaining the reverse charging member on the lancet carrier. A portionof the reverse charging member 102 engages and thus forms a portion ofthe charging mechanism that retracts the lancet carrier 80 uponactuation of the charging button 60, as described in more detail below.The reverse charging member 102 can be provided by a separate partassembled to the lancet carrier 80 (as depicted), or its features can beincorporated into the lancet carrier and thus form an integral partthereof. Therefore, as used herein, the reverse charging member isconsidered to be included as a part of the lancet carrier, sointeraction of the charging mechanism with the lancet carrier broadlyincludes interaction with the reverse charging member.

Referring primarily to FIGS. 6 and 8, the actuator mechanism is operableto actuate the lancing device 10 to propel the lancet 89 on the lancetcarrier 80 through the lancing stroke from a retracted/charged positionwithin the housing 20 to an extended/lancing position (shown in FIG. 9D)with at least a sharp tip portion 90 of the lancet projecting outwardlyof the lancet opening at the proximal/forward end of the housing. Theactuator mechanism includes a release actuator 30 that is activated by auser to release the lancet carrier 80 in the charged position so it canbe driven by the charged drive mechanism to propel the lancet carrierthrough the lancing stroke.

The release actuator 30 is typically in the form of a spring-biasedpush-button that projects through a distal/rearward opening in thehousing 20 to releasably engage a portion of the drive mechanism (seeFIGS. 6, 8). The release button 30 may directly engage the lancetcarrier 80 (as depicted) or indirectly engage it via another portion ofthe drive mechanism. The release button 30 retains the drive mechanismin the charged position when not depressed and releases the drivemechanism when depressed. In the depicted embodiment, the release button30 is generally ring-shaped and defines a first axial bore 32 extendingtherethrough that receives therein the lancet carrier 80. A secondlateral bore 34 is formed in a portion of the release button 30(generally opposite the actuating portion projecting through the housingshell 22 a) to provide engagement with a protrusion 85 that projectsfrom the bottom side of the lancet carrier 80 (see FIG. 6). As such,retraction of the lancet carrier 80 causes the second lateral bore 34 toengage and retain the protrusion 85, thus retaining the lancet carrier80 in a charged position. Additionally or alternatively, a portion ofthe release button 30 can include one or more resilient fingers 36 forbiasing against the inner drive core 70 so that the attached theretolancet carrier 80 is retained in the charged state when retracted andreleased when the release button 30 is actuated.

In other embodiments, another conventional actuator mechanism can beincluded. For example, in some embodiments the release actuator is inthe form of a structure other than a ring-shaped push-button, forexample, a spring-biased slide member or a spring-biased push-buttonthat is L-shaped. And in other embodiments, the lancet carrier (oranother portion of the drive mechanism) and the actuator mechanisminclude other retaining elements that cooperate to releasably retain thelancet carrier in the charged position, such as a female element on thelancet carrier and a cooperating male element on the release actuator.In other embodiments, the release actuator is configured torelease/actuate the drive mechanism in another way such as by a pulling,sliding, or twisting motion. In yet other embodiments, the actuatormechanism is modified and included in the charging mechanism withmodifications such that releasing the depressed charging button(described below) causes the charged lancet carrier to be released tothereby initiate the lancing stroke.

Referring primarily to FIGS. 4-8, the charging mechanism cooperates withthe drive mechanism to retract the lancet carrier 80 to the chargedposition. The charging mechanism includes a user-actuated chargingbutton 60, a portion of the reverse charging member 102, and apush-to-pull motion-conversion member 110 operably coupling themtogether. The charging button 60 and the reverse charging member 102 areconstrained to travel along an axis generally parallel to (including thesame as) the axis of the lancing stroke of the lancet carrier 80. Forexample, the housing 20 can include guidance features to transverselyconstrain the charging button 60 and the reverse charging member 102 butpermit axial their translation. Such features include longitudinalchannels slidably receiving tabs or pins, as well as other conventionalaxial-translation guidance features well-known in the art. Theuser-engaged actuating portion of the charging button 60 can be in-linewith the axis of the lancing stroke (as depicted) or laterally offsetfrom it (e.g., a transverse-extending arm). The conversion member 110 isconstrained to move only laterally/transversely (i.e., along an axisgenerally perpendicular to the lancing stroke of the lancet carrier 80).For example, the housing 20 can include guidance features to axiallyconstrain the conversion member 110 but permit lateral/transversemovement of it. Such features include two transverse walls of thehousing that are spaced apart to receive therebetween the conversionmember so that it cannot slide axially but can transversely, as well asother conventional transverse guidance features well-known in the art.

The charging button 60 is biased to a distal/rearward ready position anddepressible (against the biasing force) in a proximal/forward directionby the user to the charged position. In the depicted embodiment, forexample, the charging mechanism includes a charge-button spring 96 thatis retained on the charging button 60 by an engagement projection 64thereof (see FIG. 6). Preferably, the projection 64 is sized to retain aportion of the spring 96 thereon so that the spring extends therefromand engages a stop projection 27 of the lower housing shell 22 b (seeFIG. 4). Throughout the charging procedure, the charging button 60 isbiased distally rearward/outward by the spring 96 (i.e., in a directiongenerally opposite the first axial-push direction D1 described below).So as the charging button 60 is depressed from the distally-extendedready position to the depressed charged position to charge the drivespring 92 of the drive mechanism, the charge-button spring 96 ischarged. A stop element, for example a flange or rim portion 61 of thecharging button 60, contacts a portion of the housing 20 to retain thecharging button on the housing and define the distally-extended readyposition. As such, after performing the charging procedure to place thelancet carrier 80 in a charged state, the now-charged spring 96 returnsthe charging button 60 to the ready position in which the flange 61contacts a portion of the housing 20 to retain charging button thereon(see FIG. 2). In other embodiments, the biasing effect on the chargingbutton is provided by a leaf spring, torsion spring, or other resilientelement retained in position relative to the charging button by the sameor other conventional retaining structures.

The conversion member 110 is movably mounted to the charging button 60and the reverse charging member 102 to convert an external push actionon the charging button by the user to an internal pull action on thereverse charging member (and thus the lancet carrier 80). The conversionmember 110 includes first and second cam surfaces that are respectivelyengaged by first and second cam-engaging surfaces of the reversecharging member 102 and the charging button 60 to convert a firstmovement of the charging button 60 in a first axial-push direction D1 toa second movement of the reverse charging member in a second/oppositeaxial-pull direction D2. In particular, pushing thetransversely-constrained charging button 60 in the first axial directionD1 causes transverse movement T1 of the axially-constrained conversionmember 110, which causes the transversely-constrained reverse chargingmember 102 to retract the lancet carrier 80 in the second axialdirection D2. The first axial direction D1 and the second axialdirection D2 are generally opposite (though not necessarily co-linear)with respect to each other.

The conversion member 110 includes a first cam surface 112 formed by(recessed in or extending from) a first side 111 thereof and a secondsurface 115 formed by (recessed in or extending from) a second side 114thereof. In the depicted embodiment, first cam surface is formed by acam slot 112 and the first cam-engaging surface is formed by a boss 107projecting from a leg portion 106 of the reverse charging member 102 andreceived in the first cam slot, and the second cam surface is formed bya slot 115 and the second cam-engaging surface is formed by a boss 65projecting from the charging button 60 and received in the second camslot. Pushing the transversely-constrained charging button 60 in thefirst direction D1 axially drives the boss 65 to slide within the secondcam slot 115, which causes the axially-constrained conversion member 110to move in the transverse direction T1. As the conversion member 110 isdriven in the transverse direction T1, the boss 107 of thetransversely-constrained reverse charging member 102 is constrainedwithin the first cam slot 112 and thereby axially driven in the seconddirection D2 to retract the lancet carrier 80 in the second directionD2. In other embodiments, the first cam-engaging surface is formed onanother portion of the lancet carrier or other element of the drivemechanism, and/or the second cam-engaging surface is formed on anotherportion of the charging member (including another element of thecharging mechanism operably coupled to the charging member).

In addition, the depicted conversion member 110 is generally box-shapedand solid, with a peripheral side 116 extending between outer edges ofthe first and second sides 111 and 114 and extending peripherally allthe way around. In other embodiments, the conversion member is generallyX-shaped, has another regular or irregular shape, and/or has a non-solidframe-like structure. For example, two cam tracks or other guidancestructures, each defining a respective one of the two cam surfaces, canbe assembled together or integrally formed together.

Referring particularly to FIG. 7, the conversion member 110 will now bedescribed in greater detail. The cam slots 112, 115 can be provided in avariety of shapes, forms, and/or configurations to provide for pullingretraction of the lancet carrier 80 by pushing actuation of the chargingbutton 60. In the depicted embodiment, the cam slots 112, 115 aregenerally linear with each defining a channel in which the respectivebosses 107 and 65 of the charging member 102 and the charging button 60movably slide. Preferably, the cam slots 112, 115 are shaped smoothlywith no sharp turns to provide the lancet carrier 80 with a smoothtransition from the neutral state (FIG. 9A), the charging state (FIG.9B), the charged state (FIG. 9C), the fully-extended state (FIG. 9D),and back to the neutral state (FIG. 9A). In other embodiments, the camslots are non-linear (e.g., curved or in an undulating/sinusoidal, otherregular, or irregular shape) or otherwise shaped to provide the desiredpush-to-pull operation of the charging mechanism. In yet otherembodiments, one or both of the cam surfaces are defined by protrusionsor side edges of the conversion member that are engaged by slots orledge surfaces of the reverse charging member and/or the chargingbutton.

In the depicted embodiment, the cam slots 112, 115 are substantiallysimilar, but oppositely arranged from each other in a generallymirror-image fashion (e.g., at about 180 degrees from each otherrelative to the longitudinal axis) to form a crisscross pattern (thoughlaterally offset from each other), such that actuation in the firstaxial-push direction D1 (that causes transverse movement T1 of theconversion member) forces the reverse charging member 102 to retract inthe second axial-pull direction D2, thereby retracting the lancetcarrier 80. In other words, the first cam slot 112 can be at an angle αfrom the longitudinal axis, and the second cam slot 115 can be at anangle β from the longitudinal axis, with the angle α having generallythe same (or a slightly larger) absolute value as angle β, but negative.For example, in one embodiment angle α is 30 degrees and angle β isnegative 23 degrees (i.e., 337 degrees).

Having described the structure of the lancing device 10, details of itsoperation will now be described with reference to FIGS. 9A-D. Generallydescribed, the sequence of operation of the lancing device 10 includesthe lancet carrier 80 moving from a neutral position (FIG. 9A), to acharged position (FIG. 9B), to a ready position (FIG. 9C), to a fullyextended position of the lancing stroke (FIG. 9D), and back to theneutral position (FIG. 9A). In the neutral position (FIG. 9A), theconversion member 110 is positioned on one side (laterally offset fromthe longitudinal axis) within the housing 20, with the boss 107 of thereverse charging member 102 engaged with the first cam slot 112, andwith the boss 65 of the charging button 60 engaged within the second camslot 115. The charge-button spring 96 biases the charging button 60distally/rearwardly to the extended position and the charging button'sflange or rim 61 contacts the housing 20 to remain retained therein.

As shown in FIG. 9B, to charge the lancing device 10, the chargingbutton 60 is pressed forward relative to the housing 20 in the firstaxial-push direction D1 to the depressed position, which causes the boss65 of the charging button to move longitudinally within the angledsecond cam slot 115, which causes the conversion member 110 to move inthe transverse direction T1. As the conversion member shifts laterallyin the transverse direction T1, the angled first cam slot 112 drives theboss 107 of the reverse charging member 102 rearwardly, which causes thelancet carrier 80 to retract in the second axial-push direction D2. Theretraction of the lancet carrier 80 causes the protrusion 85 extendingtherefrom to move into retaining engagement with the second bore 34 ofthe release button 30, thereby retaining the lancet carrier 80 in thecharged state.

As shown in FIG. 9C, when the charging button 60 is released, thecharge-button spring 96 returns the charging button to its extendedposition. As the charging button 60 so returns, its boss 65 drives thecam slot 115 of the conversion member 110 to cause the conversion memberto move in the lateral T2 direction back to its original neutralposition. The lancing device 10 is now charged and ready to be used fora lancing procedure. As shown in FIG. 9D, when the release button 30 ispressed to initiate a lancing procedure, its second bore 34 is removedfrom engagement with the protrusion 85 of the lancet carrier 80, therebyfreeing the drive spring 92 to propel the lancet carrier along thelancing stroke to the extended position with the sharp tip portion 90 ofthe lancet 89 projecting out of the housing. This action charges thereturn spring 94, which then discharges to retract the lancet carrier 80back to the neutral position of FIG. 9A. Optionally, removal of theendcap 40 allows for actuation of the ejection mechanism 50 to removethe used lancet 89 and replace it with a new lancet.

FIGS. 10-12D show a lancing device 200 according to a second exampleembodiment of the present invention. The lancing device 200 of thisembodiment is substantially similar to that of the first embodimentdescribed above. Thus, the lancing device 200 includes a chargingmechanism, an actuator mechanism, a drive mechanism, and a housing forthese components, with the drive mechanism including a lancet carrierthat carries a lancet, and with all these components except the chargingmechanism being the same or substantially similar to those of thelancing device 10 described above.

The charging mechanism of this embodiment includes a rack-and-pinionpush-to-pull mechanism, rather than the cam-driven push-to-pullmechanism of the lancing device 10 of the first embodiment. Generallydescribed, the rack-and-pinion charging mechanism includes a chargingbutton 260 with a rack gear 265, a reverse charging member 302 (e.g.,L-shaped link) with a rack gear 307, and a pinion gear 310 rotatablyengaged therebetween. Pushing the charging button 260 causes theattached rack gear 265 to translate longitudinally in the firstaxial-push direction D1, which drives the engaged pinion gear 310 torotate in a first angular direction (e.g., counter-clockwise), which inturn drives the reverse charging member 302 in the second oppositeaxial-pull direction D2. The exact configuration, size, and/or shape ofthe components of the rack-and-pinion charging mechanism can be selectedand/or modified as desired.

The charging button 260 is generally similar to the charging button 60of the first embodiment described above, except a noted below. In thedepicted embodiment, the charging button 260 includes an elongate guidearm 262 extending longitudinally therefrom for slidably engaging a guidechannel 227 (e.g., formed by the housing sidewall and a longitudinalinternal wall) or other engagement feature of the lower housing shell222 b. In one form, the elongate guide arm 262 is shaped to receiveguidance from the channel 227 while allowing the rack 307 to remainoperative therein. The first rack 265 is formed on a portion of thecharging button 260 and has a series of teeth 266 projecting therefrom.Optionally, a portion of the charging button 260 may include an orificefor allowing the rack 307 to extend therethrough when the chargingbutton is actuated. For example, to ensure the rack 307 is fullyretracted to charge the drive spring 292, an opening 267 may be providedto prevent contact between the rack 307 and the button 260.

The reverse charging member 302 is generally similar to the reversecharging member 102 as described above, except as noted below. Asdepicted, the second rack 307 extends from a portion of the leg portion306 of the reverse charging member 302 in a direction generally parallelwith the same, and includes a series of teeth 308 projecting in anopposite/facing direction from the teeth 266 of the first rack 265. Theracks 265, 307 are configured such that the respective teeth 266, 308projecting therefrom engage teeth 314 of the pinion 310 rotatablymounted therebetween. As described above, the charging button 260 andthe reverse charging member 302 are axially constrained to traverse onlyalong an axis generally parallel to the advancement and retraction ofthe lancet carrier 280.

The pinion 310 is rotatably mounted to the housing, for example by abore 312 that receives a post 316 extending inward from the lowerhousing shell 222 b. In example embodiments, the post 316 is laterallyoffset from the axis defining the advancement and retraction of thelancet carrier. The teeth 314 of the pinion 310 engage the teeth 265,308 of the racks 265, 307 so that linear motion of the second rackproduces an opposite linear motion of the first rack.

FIGS. 12A-D show the sequential operation of the lancing device 200. Thesequence of operation of the lancing device 200 generally includes thelancet carrier 280 translating from a neutral position (FIG. 12A), to acharged position (FIG. 12B), to a ready position (FIG. 12C), to a fullyextended position of the lancing stroke (FIG. 12D), and back to theneutral position (FIG. 12A).

In the neutral position (FIG. 12A), the teeth 314 of the pinion 310 areengaged with both a portion of the rack 265 of the charging button 260and with a portion of the rack 307 of the reverse charging member 302.The charge-button spring 296 biases the charging button 260 rearwardlywherein the flange or rim 261 contacts portions of the housing to remainretained therein. As best seen in FIG. 12B, the user-actuated portion ofthe charging button is pressed into the device 200 (first direction D1),causing the rack 265 to rotationally drive the pinion (e.g.,counter-clockwise), which translationally drives and retracts the rack307 of the reverse charging member 302 (second direction D2). Assimilarly described above, the release button 230 provides releasableengagement with a portion of the lancet carrier to maintain a readyposition (FIG. 12C) until actuated by being pressed therein to removethe projection 285 from within the second bore 234 (see FIG. 11). Aftercharging, the biasing spring 296 biases the charging button 260 toproject outwardly wherein the flange 261 engages portions of the housing220.

When the release button 230 is pressed, the second bore 234 of the sameis removed from engagement with the protrusion 285, thereby allowing thedrive spring 292 to propel the lancet carrier 80 along the lancingstroke wherein the sharp tip portion 290 of the lancet 289 projectsexternal the housing (FIG. 12D). Preferably, the return spring 294 orother biasing members therein cause retraction of the lancet carrierback to the neutral position (FIG. 12A). Also optional, removal of theendcap 240 allows for actuation of the ejection mechanism 250 to removethe used lancet and replace with a new lancet.

In additional example embodiments, the present invention relates to amethod of charging a lancing device. The method preferably comprisesslidably mounting a charging mechanism within a portion of the lancingdevice, movably mounting a conversion member with a portion of thecharging mechanism, movably mounting a portion of the lancet carrierwith the conversion member, pressing the charging mechanism into thelancing device, forcing movement of the conversion member in a directiontransverse to the movement of the charging mechanism, and moving thelancet carrier in a direction generally opposite the direction ofmovement of the charging mechanism subsequently charging the lancingdevice.

While the invention has been described with reference to preferred andexample embodiments, it will be understood by those skilled in the artthat a variety of modifications, additions and deletions are within thescope of the invention, as defined by the following claims.

What is claimed is:
 1. A lancing device for propelling a lancet througha lancing stroke, the lancing device comprising: a housing including anaxial bore; a drive mechanism including a lancet carrier and a drivespring, the lancet carrier holding the lancet and translatable axiallywithin the housing through the lancing stroke, and the drive springadapted to propel the lancet carrier through the lancing stroke; and acharging mechanism adapted to retract the lancet carrier to a chargedposition and including a charging button having a first rack gear, areverse charging member having a second rack gear, and a pinion gearrotatably engaged between the first and second rack gears, and whereinmovement of the charging button in a first axial direction causesrotation of the pinion gear, which in turn causes movement of thereverse charging member and lancet carrier coupled thereto in a secondaxial direction generally opposite the first axial direction to retractthe lancet carrier to a charged position, wherein the charging buttonincludes an orifice allowing the first rack gear to extend through thehousing when the charging button is actuated.
 2. The lancing device ofclaim 1, wherein the charging button is movable between an extendedposition and a depressed position, and is spring-biased toward theextended position.
 3. The lancing device of claim 1, wherein the housingcomprises a guidance feature.
 4. The lancing device of claim 3, whereinthe charging button comprises an elongate guide arm extendinglongitudinally therefrom for slidably engaging the guidance feature. 5.The lancing device of claim 4, wherein the elongate guide arm is shapedto receive guidance from the guidance feature while allowing the secondrack gear to remain operative.
 6. The lancing device of claim 1, whereinthe orifice is adapted to prevent contact between the charging buttonand the second rack gear.
 7. The lancing device of claim 1, wherein thecharging button and the reverse charging member are axially constrainedto traverse only along an axis generally parallel to advancement andretraction of the lancet carrier.
 8. The lancing device of claim 1,wherein the pinion gear is rotatably mounted to the housing by a borethat receives a post extending inward from the housing.
 9. The lancingdevice of claim 8, wherein the post is laterally offset from an axisdefining advancement and retraction of the lancet carrier.
 10. Acharging mechanism for a lancing device comprising a lancet carrier thatcarries a lancet through a lancing stroke, the charging mechanismcomprising: a charging button slidably coupled to the lancing device topermit axial movement between an extended position and a depressedposition and including a first rack gear; a reverse charging membercoupled to the lancet carrier and including a second rack gear; and apinion gear rotatably engaged between the first and second rack gears,wherein movement of the charging button in a first axial directioncauses rotation of the pinion gear, which in turn causes movement of thereverse charging member and lancet carrier coupled thereto in a secondaxial direction generally opposite the first axial direction to retractthe lancet carrier to a charged position; wherein the charging mechanismis situated in a housing and wherein the housing comprises a guidancefeature; and wherein the charging button includes an orifice allowingthe first rack gear to extend through the housing when the chargingbutton is actuated.
 11. The charging mechanism of claim 10, wherein thecharging button is movable between an extended position and a depressedposition, and is spring-biased toward the extended position.
 12. Thecharging mechanism of claim 10, further comprising an elongate guide armextending longitudinally therefrom for slidably engaging the guidancefeature.
 13. The charging mechanism of claim 12, wherein the elongateguide arm is shaped to receive guidance from the guidance feature whileallowing the second rack gear to remain operative.
 14. The lancingdevice of claim 10, wherein the orifice is adapted to prevent contactbetween the charging button and the second rack gear.
 15. The chargingmechanism of claim 10, wherein the charging button and the reversecharging member are axially constrained to traverse only along an axisgenerally parallel to advancement and retraction of the lancet carrier.16. The charging mechanism of claim 10, wherein the pinion gear isrotatably mounted to the housing by a bore that receives a postextending inward from the housing.
 17. The lancing device of claim 16,wherein the post is laterally offset from an axis defining advancementand retraction of the charging button.